Reservoir pressure equalization systems and methods

ABSTRACT

Various embodiments of the present invention are directed to equalizing pressure in a reservoir containing fluidic media, possibly due to imperfect installation of the reservoir or an external influence such as an altitude or a temperature change. In various embodiments, fluidic media may be expelled from the reservoir through a needle and contained in an interior volume of a pierceable member before the needle pierces the pierceable member to establish a flow path to a user. In other embodiments, fluidic media may be expelled through a port of the reservoir into a chamber. In further embodiments, fluidic media may be expelled through a channel in a plunger head and out a passage in the reservoir when the channel and passage are aligned. In other embodiments, fluidic media may be expelled through a valve, and the valve may be pierceable by a needle to establish a flow path to the user.

CROSS-REFERENCE TO RELATED PATENT APPLICATIONS

This application is a Division of U.S. application Ser. No. 13/411,278,filed Mar. 2, 2012, which is a Division of U.S. Ser. No. 11/965,578,filed Dec. 27, 2007, incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

Embodiments of the present invention relate generally to systems andmethods with reservoirs and, in specific embodiments, to systems andmethods allowing for pressure equalization of fluidic media containedwithin the reservoirs.

2. Related Art

According to modern medical techniques, certain chronic diseases may betreated by delivering a medication or other substance to the body of apatient. For example, diabetes is a chronic disease that is commonlytreated by delivering defined amounts of insulin to a patient atappropriate times. Traditionally, manually operated syringes and insulinpens have been employed for delivering insulin to a patient. Morerecently, modern systems have been designed to include programmablepumps for delivering controlled amounts of medication to a patient.

Pump type delivery devices have been configured in external devices,which connect to a patient, and have also been configured in implantabledevices, which are implanted inside of the body of a patient. Externalpump type delivery devices include devices designed for use in astationary location, such as a hospital, a clinic, or the like, andfurther include devices configured for ambulatory or portable use, suchas devices that are designed to be carried by a patient, or the like.External pump type delivery devices may contain reservoirs of fluidicmedia, such as, but is not limited to, insulin. External pump typedelivery devices may be connected in fluid flow communication to apatient or user, for example, through a suitable hollow tubing. Thehollow tubing may be connected to a hollow needle that is designed topierce the skin of the patient and to deliver fluidic media therethrough. Alternatively, the hollow tubing may be connected directly tothe patient as through a cannula, or the like.

Examples of some external pump type delivery devices are described inthe following references: (i) Published PCT Application WO 01/70307(PCT/US01/09139), entitled “Exchangeable Electronic Cards for InfusionDevices”; (ii) Published PCT Application WO 04/030716(PCT/US2003/028769), entitled “Components and Methods for PatientInfusion Device”; (iii) Published PCT Application WO 04/030717(PCT/US2003/029019), entitled “Dispenser Components and Methods forInfusion Device”; (iv) U.S. Patent Application Pub. No. 2005/0065760,entitled “Method for Advising Patients Concerning Doses Of Insulin”; and(v) U.S. Pat. No. 6,589,229, entitled “Wearable Self-Contained DrugInfusion Device”, each of which is incorporated by reference herein inits entirety.

As compared to syringes and insulin pens, pump type delivery devices canbe significantly more convenient to a patient, in that doses of insulinmay be calculated and delivered automatically to a patient at any timeduring the day or night. Furthermore, when used in conjunction withglucose sensors or monitors, insulin pumps may be automaticallycontrolled to provide appropriate doses of fluidic media at appropriatetimes of need, based on sensed or monitored levels of blood glucose. Asa result, pump type delivery devices have become an important aspect ofmodern medical treatments of various types of medical conditions, suchas diabetes, and the like. As pump technologies improve and doctors andpatients become more familiar with such devices, external medicalinfusion pump treatments are expected to increase in popularity and areexpected to increase substantially in number over the next decade.

However, one of the problems with pump type delivery devices is that abolus of fluidic media could be delivered inadvertently to the patientin a case where the reservoir of fluidic media is pressurized. FIG. 13illustrates a conventional reservoir system 700. The reservoir system700 may include a reservoir 710 with an interior volume 715 filled withfluidic media, a plunger head 720, a plunger shaft 725, and a driveshaft772 mechanically connected to a drive motor 774. The reservoir 710 mayinclude a self-sealing septum 711. When the reservoir 710 is inserted inthe reservoir system 700, the plunger shaft 725 mechanically coupleswith the driveshaft 772 by use of complementing mating parts, such asthreads, for example. If the complementing threads of the plunger shaft725 and the driveshaft 772 are not perfectly aligned, the plunger shaft725 shifts a small distance, such as a half thread forward or backward,so that the threads can align and couple together. Accordingly, theplunger head 720, which is connected to the plunger shaft 725, is moveda half thread forward or backward within the reservoir 710. If theplunger head 720 is moved forward, pressure in the interior volume 715of the reservoir 710 is increased. As a result, this could cause thereservoir system 700 inadvertently to pump a small bolus of fluidicmedia to a user once a fluid path between the reservoir system 700 andthe user is established. Alternatively, the interior volume 715 of thereservoir 710 could become pressurized due to a change in an externalinfluence such as an altitude or a temperature as well, which could alsolead to an inadvertent bolus of fluid being delivered to the user oncethe fluid path between the reservoir system 700 and the user isestablished. The opposite effect is true for a system that draws theplunger head backwards, establishing a negative pressure in thereservoir. In this case, bodily fluids may be drawn into the fluid pathor reservoir when the fluid system is fully connected.

SUMMARY OF THE INVENTION

Various embodiments of the present invention are directed to equalizingpressure in a reservoir containing fluidic media. This may preventpatients from inadvertently receiving boluses of fluidic media becauseof increased pressure within a reservoir of a medical device due to, forexample, imperfect alignment of a plunger shaft and a driveshaft withinthe medical device, or a change in an external influence, such as analtitude or a temperature change. Additionally, it may prevent thesystem from drawing bodily fluids into the reservoir if the reservoir isbiased with a negative pressure.

A system for equalizing pressure in a reservoir in accordance with anembodiment of the present invention may include, but is not limited to,a structure, a needle, and a pierceable member. The structure may have achamber. The needle may be connectable to the reservoir for allowingfluidic media contained in the reservoir to flow through the needle whenthe needle is connected to the reservoir. The pierceable member may bemoveable within the chamber and pierceable by the needle. The pierceablemember may have an interior volume for containing fluidic media expelledfrom the reservoir before the pierceable member is pierced by theneedle. In some embodiments, the interior volume of the pierceablemember may allow for containing fluidic media that flows through theneedle from the reservoir before the pierceable member is pierced by theneedle. Fluidic media may be expelled from the reservoir in a case wherea pressure difference exists between the reservoir and the chamber. Insome embodiments, fluidic media may be expelled from the reservoir in acase where a pressure difference exists between the reservoir and theinterior volume of the pierceable member. An end of the needle may belocated at least substantially within the interior volume of thepierceable member before the pierceable member is pierced by the needle.A cross-section of the pierceable member may be U-shaped.

The system may further include a first housing portion and a secondhousing portion. The first housing portion may be adapted to be carriedby a user. The second housing portion may be configured to beselectively operatively engaged with and disengaged from the firsthousing portion. The structure may be supported by one of the first andsecond housing portions. The pierceable member may be positioned to bepierced by the needle when the first housing portion and the secondhousing portion are operatively engaged. The needle may be positioned toenter the other of the first and second housing portions from the one ofthe first and second housing portions when the first housing portion andthe second housing portion are operatively engaged.

The pierceable member may have a first end and a second end. The firstend may be for contacting the other of the first and second housingportions from the one of the first and second housing portions when thefirst housing portion and the second housing portion are operativelyengaged. The second end may be located on an opposite side of thepierceable member from the first end.

The chamber may have a first portion and a second portion. The firstportion of the chamber may be adjacent to the second end of thepierceable member. The first portion of the chamber may be forcontaining fluidic media in a case where fluidic media flows out of theinterior volume of the pierceable member. The first portion of thechamber may be located between the pierceable member and the reservoir.The second portion of the chamber may be adjacent to an opposite side ofthe pierceable member from the first portion of the chamber. The secondportion of the chamber may be for containing fluidic media in a casewhere fluidic media flows out of the first portion of the chamber. Thepierceable member may further include a seal member. The structure mayhave an opening that communicates with the chamber. The opening mayallow for fluidic media to be purged from the chamber in a case wherefluidic media flows out of the interior volume of the pierceable member.

The system may further include a bias member. The bias member may bearranged to impart a bias force on the pierceable member. The biasmember may be a spring. In other embodiments, the pierceable member mayhave a resiliently flexible portion. The resiliently flexible portionmay be for providing a bias force on the pierceable member to maintainthe pierceable member within the chamber. In various embodiments, theneedle may have a longitudinal dimension and a central axis along thelongitudinal dimension. The interior volume of the pierceable member maybe curved concavely relative to the central axis of the needle. Invarious embodiments, at least one seal member may be positioned betweenthe structure and the pierceable member.

A method for equalizing a pressure within a reservoir may include, butis not limited to, providing a structure having a chamber, locating aneedle connectable to the reservoir for allowing fluidic media containedin the reservoir to flow through the needle when the needle is connectedto the reservoir, and locating a pierceable member moveable within thechamber, where the pierceable member is pierceable by the needle, andwhere the pierceable member has an interior volume for containingfluidic media expelled from the reservoir before the pierceable memberis pierced by the needle.

In an embodiment of a system for equalizing pressure, the system mayinclude, but is not limited to, a reservoir, a plug, and a structure.The reservoir may have a port and an interior volume for containingfluidic media. The plug may be positioned relatively offset to the portof the reservoir. The plug may be for closing the port of the reservoirwhen the plug is in a closed position. The plug may comprise one of aflapper valve and a disc valve. The structure may have a chamber in flowcommunication with the interior volume of the reservoir. The chamber mayallow for collecting fluidic media expelled from the interior volume ofthe reservoir through the port in a case where a pressure differenceexists between the interior volume of the reservoir and the chamberbefore the plug is held in the closed position.

The system may further include a first housing portion and a secondhousing portion. The first housing portion may be adapted to be carriedby a user. The second housing portion may be configured to beselectively operatively engaged with and disengaged from the firsthousing portion. The reservoir may be supported by one of the first andsecond housing portions. The plug may be positioned to close the port ofthe reservoir when the first housing portion and the second housingportion are operatively engaged. The other of the first and secondhousing portions from the one of the first and second housing portionsmay have a first surface for moving and holding the plug in the closedposition when the first housing portion and the second housing portionare operatively engaged.

The system may further include a needle. The needle may be supported bythe other of the first and second housing portions from the one of thefirst and second housing portions. The needle may be for piercing aportion of the reservoir and entering the interior volume of thereservoir when the first housing portion and the second housing portionare operatively engaged. The needle may allow for fluidic mediacontained in the interior volume of the reservoir to flow through theneedle when the needle is in the interior volume of the reservoir. Insome embodiments, the portion of the reservoir pierced by the needlewhen the first housing portion and the second housing portion areoperatively engaged may be the plug.

The system may further include a membrane configured to expand toincrease the volume of the chamber in a case where the chambersufficiently fills with fluidic media. The membrane may be anelastomeric membrane. The system may include one of a hydrophobic filterand a hydrophilic filter. The chamber may be located within thereservoir. In some embodiments, the chamber may be located outside ofthe reservoir. The structure may have an opening that communicates withthe chamber, where the opening may allow for fluidic media to be purgedfrom the chamber.

A method for equalizing pressure may include, but is not limited to,providing a reservoir having a port and an interior volume forcontaining fluidic media, locating a plug positioned relatively offsetto the port of the reservoir, where the plug allows for closing the portof the reservoir when the plug is in a closed position, and locating astructure having a chamber in flow communication with the interiorvolume of the reservoir, where the chamber allows for collecting fluidicmedia expelled from the interior volume of the reservoir from the portin a case where a pressure difference exists between the interior volumeof the reservoir and the chamber before the plug is held in the closedposition.

In an embodiment of a system for equalizing pressure, the system mayinclude, but is not limited to, a reservoir and a plunger head. Thereservoir may have a passage and an interior volume for containingfluidic media. The plunger head may have a first surface and a secondsurface. The plunger head may have a channel connecting the firstsurface and the second surface. The plunger head may be moveable withinthe reservoir to align the channel in the plunger head and the passagein the reservoir. When the channel in the plunger head and the passagein the reservoir are aligned and a pressure difference exists betweenthe interior volume of the reservoir and the passage, fluidic media maybe expelled from the interior volume of the reservoir through thepassage.

In various embodiments, the interior volume allows for containingfluidic media. In some embodiments, the reservoir may have a secondinterior volume. The plunger head may be located between the interiorvolume of the reservoir and the second interior volume of the reservoir.The first surface of the plunger head may be in contact with fluidicmedia when fluidic media is in the interior volume of the reservoir.

In various embodiments, the passage in the reservoir and the channel inthe plunger head may be aligned at a first position of the plunger headin the reservoir. The plunger head may be advanceable from the firstposition to a second position. The passage in the reservoir and thechannel in the plunger head may be disaligned when the plunger head isin the second position.

In various embodiments, the system may further include a first housingportion and a second housing portion. The first housing portion may beadapted to be carried by a user. The second housing portion may beconfigured to be selectively operatively engaged with and disengagedfrom the first housing portion. The reservoir may be supported by one ofthe first and second housing portions.

In various embodiments, the system may further include a mating piece.The mating piece may be supported by the other of the first and secondhousing portions from the one of the first and second housing portions.The mating piece may be for closing the passage when the first housingportion and the second housing portion are operatively engaged. Thesystem may also include a needle. The needle may be supported by theother of the first and second housing portions from the one of the firstand second housing portions. The needle may be for piercing thereservoir and entering the interior volume of the reservoir when thefirst housing portion and the second housing portion are operativelyengaged. The needle may be for allowing fluidic media contained in theinterior volume of the reservoir to flow through the needle when theneedle is in the interior volume of the reservoir. The plunger head maybe advanceable in the reservoir from the first position to the secondposition before the first housing portion and the second housing portionare operatively engaged. The first surface of the plunger head and thesecond surface of the plunger head may be perpendicular to each other.

In various embodiments, the system may further include a valvepositioned relative to an end of the channel in the plunger head. Thevalve may allow for closing the channel in the plunger head when thevalve is in a closed position. In some embodiments, the system mayinclude a valve positioned relative to an end of the passage in thereservoir. The valve may allow for closing the passage in the reservoirwhen the valve is in a closed position.

In various embodiments, the system may further include a structure. Thestructure may have a chamber connected to the passage. The chamber mayallow for collecting fluidic media that flows through the passage in thereservoir. Fluidic media may flow through the passage when the channelin the plunger head and the passage in the reservoir are aligned and apressure difference exists between the interior volume of the reservoirand the passage. The structure may include a membrane configured toexpand to increase the volume of the chamber in a case where the chambersufficiently fills with fluidic media. The membrane may comprise anelastomeric membrane. The system may include one of a hydrophobic filterand a hydrophilic filter. The chamber may be located within thereservoir. In some embodiments, the chamber may be located outside ofthe reservoir. The system may further include at least one seal memberpositioned between the plunger head and the reservoir.

A method for equalizing pressure may include, but is not limited to,providing a reservoir having a passage and an interior volume forcontaining fluidic media, and locating a plunger head having a firstsurface and a second surface, where the plunger head has a channelconnecting the first surface and the second surface, the plunger head ismoveable within the reservoir to align the channel in the plunger headand the passage in the reservoir, and when the channel in the plungerhead and the passage in the reservoir are aligned and a pressuredifference exists between the interior volume of the reservoir and thepassage, fluidic media is expelled from the interior volume of thereservoir through the passage.

A system for equalizing pressure may include, but is not limited to, amating piece, a needle, a reservoir, and at least one valve. The needlemay be supported by the mating piece. The reservoir may have an interiorvolume for containing fluidic media. The mating piece may be configuredto be selectively operatively engaged with and disengaged from thereservoir. The reservoir may have a port for allowing fluidic media tobe expelled from the interior volume of the reservoir before thereservoir and the mating piece are operatively engaged. The at least onevalve may be positioned relative to an end of the port. The at least onevalve may be for closing the port when the mating piece and thereservoir are operatively engaged. The needle may be for piercing the atleast one valve and entering the interior volume of the reservoir whenthe reservoir and the mating piece are operatively engaged. The needlemay allow for fluidic media contained in the interior volume of thereservoir to flow through the needle when the needle is in the interiorvolume of the reservoir.

In various embodiments, the system may further include a structurehaving a chamber connected to the port of the reservoir. The chamber mayallow for collecting fluidic media expelled from the interior volume ofthe reservoir before the reservoir and the mating piece are operativelyengaged. Fluidic media may be expelled from the interior volume of thereservoir before the reservoir and the mating piece are operativelyengaged in a case where a pressure difference exists between thereservoir and the chamber. The system may further include a membraneconfigured to expand to increase the volume of the chamber in a casewhere the chamber sufficiently fills with fluidic media. The membranemay comprise an elastomeric membrane. The system may include one of ahydrophobic filter and a hydrophilic filter.

In various embodiments, the system may further include a first housingportion and a second housing portion. The first housing portion may beadapted to be carried by a user. The second housing portion may beconfigured to be selectively operatively engaged with and disengagedfrom the first housing portion. The reservoir may be supported by one ofthe first and second housing portions. The mating piece may be supportedby the other of the first and second housing portions from the one ofthe first and second housing portions. The mating piece and thereservoir may be operatively engaged when the first housing portion andthe second housing portion are operatively engaged.

In various embodiments, the at least one valve may have a moveableportion. The moveable portion may be moveable between an open positionand a closed position such that the at least one valve is moveable bythe mating piece from the open position to the closed position to closethe port of the reservoir when the reservoir and the mating piece areoperatively engaged. In some embodiments, the moveable portion of the atleast one valve may be pierceable by the needle when the reservoir andthe mating piece are operatively engaged.

In various embodiments, the at least one valve may be arranged to beheld closed by the mating piece to close the port of the reservoir whenthe reservoir and the mating piece are operatively engaged. In someembodiments, the at least one valve may comprise one of a flapper valveand a loose fitting cap. In other embodiments, the at least one valvemay comprise a covering that seals the port of the reservoir. Thecovering may have an opening. The opening may be for allowing fluidicmedia to be expelled from the interior volume of the reservoir beforethe reservoir and the mating piece are operatively engaged. The coveringmay have a second valve positioned relative to an end of the opening inthe covering. The second valve may be arranged to be held closed by themating piece to close the opening in the covering when the reservoir andthe mating piece are operatively engaged. In other embodiments, theneedle may be positioned to enter the opening when the reservoir and themating piece are operatively engaged.

A method for equalizing pressure may include, but is not limited to,providing a mating piece, locating a needle supported by the matingpiece, locating a reservoir having an interior volume for containingfluidic media, where the mating piece is configured to be selectivelyoperatively engaged with and disengaged from the reservoir, and thereservoir has a port for allowing fluidic media to be expelled from theinterior volume of the reservoir before the reservoir and the matingpiece are operatively engaged, and locating at least one valve relativeto an end of the port, where the at least one valve allows for closingthe port when the mating piece and the reservoir are operativelyengaged. The needle allows for piercing the at least one valve andentering the interior volume of the reservoir when the reservoir and themating piece are operatively engaged. The needle allows for fluidicmedia contained in the interior volume of the reservoir to flow throughthe needle when the needle is in the interior volume of the reservoir.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a generalized representation of a system inaccordance with an embodiment of the present invention;

FIG. 2 illustrates an example of a system in accordance with anembodiment of the present invention;

FIG. 3 illustrates an example of a delivery device in accordance with anembodiment of the present invention;

FIG. 4 illustrates a delivery device in accordance with an embodiment ofthe present invention;

FIG. 5A illustrates a durable portion of a delivery device in accordancewith an embodiment of the present invention;

FIG. 5B illustrates a section view of a durable portion of a deliverydevice in accordance with an embodiment of the present invention;

FIG. 5C illustrates a section view of a durable portion of a deliverydevice in accordance with an embodiment of the present invention;

FIG. 6A illustrates a disposable portion of a delivery device inaccordance with an embodiment of the present invention;

FIG. 6B illustrates a section view of a disposable portion of a deliverydevice in accordance with an embodiment of the present invention;

FIG. 6C illustrates a section view of a disposable portion of a deliverydevice in accordance with an embodiment of the present invention;

FIG. 7A illustrates a cross-sectional view of a delivery device inaccordance with an embodiment of the present invention;

FIG. 7B illustrates a cross-sectional view of a reservoir assembly inaccordance with an embodiment of the present invention;

FIG. 7C illustrates a cross-sectional view of a reservoir assemblyconnected to a base assembly in accordance with an embodiment of thepresent invention;

FIG. 8A illustrates a cross-sectional view of a system for equalizingpressure in a first position in accordance with an embodiment of thepresent invention;

FIG. 8B illustrates a cross-sectional view of a system for equalizingpressure in a second position in accordance with an embodiment of thepresent invention;

FIG. 8C illustrates a cross-sectional view of a reservoir in accordancewith an embodiment of the present invention;

FIG. 9A illustrates a cross-sectional view of a system for equalizingpressure in accordance with an embodiment of the present invention;

FIG. 9B illustrates a cross-sectional view of a system for equalizingpressure in accordance with an embodiment of the present invention;

FIG. 9C illustrates a cross-sectional view of a reservoir in accordancewith an embodiment of the present invention;

FIG. 9D illustrates a cross-sectional view of a system for equalizingpressure in accordance with an embodiment of the present invention;

FIG. 10A illustrates a cross-sectional view of a system for equalizingpressure in a first position in accordance with an embodiment of thepresent invention;

FIG. 10B illustrates a cross-sectional view of a system for equalizingpressure in a second position in accordance with an embodiment of thepresent invention;

FIG. 10C illustrates a cross-sectional view of a reservoir in accordancewith an embodiment of the present invention;

FIG. 11A illustrates a cross-sectional view of a system for equalizingpressure in a first position in accordance with an embodiment of thepresent invention;

FIG. 11B illustrates a cross-sectional view of a system for equalizingpressure in a second position in accordance with an embodiment of thepresent invention;

FIG. 12A illustrates a cross-sectional view of a system for equalizingpressure in a first position in accordance with an embodiment of thepresent invention;

FIG. 12B illustrates a cross-sectional view of a system for equalizingpressure in a second position in accordance with an embodiment of thepresent invention;

FIG. 12C illustrates a cross-sectional view of a reservoir in accordancewith an embodiment of the present invention; and

FIG. 13 illustrates a cross-sectional view of a conventional pumpdelivery device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 illustrates a generalized representation of a system 10 inaccordance with an embodiment of the present invention. The system 10includes a delivery device 12. The system 10 may further include asensing device 14, a command control device (CCD) 16, and a computer 18.In various embodiments, the delivery device 12 and the sensing device 14may be secured at desired locations on the body 5 of a patient or user7. The locations at which the delivery device 12 and the sensing device14 are secured to the body 5 of the user 7 in FIG. 1 are provided onlyas representative, non-limiting, examples.

The delivery device 12 is configured to deliver fluidic media to thebody 5 of the user 7. In various embodiments, fluidic media includes aliquid, a fluid, a gel, or the like. In some embodiments, fluidic mediaincludes a medicine or a drug for treating a disease or a medicalcondition. For example, fluidic media may include insulin for treatingdiabetes, or may include a drug for treating pain, cancer, a pulmonarydisorder, HIV, or the like. In some embodiments, fluidic media includesa nutritional supplement, a dye, a tracing medium, a saline medium, ahydration medium, or the like.

The sensing device 14 includes a sensor, a monitor, or the like, forproviding sensor data or monitor data. In various embodiments, thesensing device 14 may be configured to sense a condition of the user 7.For example, the sensing device 14 may include electronics and enzymesreactive to a biological condition, such as a blood glucose level, orthe like, of the user 7. In various embodiments, the sensing device 14may be secured to the body 5 of the user 7 or embedded in the body 5 ofthe user 7 at a location that is remote from the location at which thedelivery device 12 is secured to the body 5 of the user 7. In variousother embodiments, the sensing device 14 may be incorporated within thedelivery device 12.

Each of the delivery device 12, the sensing device 14, the CCD 16, andthe computer 18 may include transmitter, receiver, or transceiverelectronics that allow for communication with other components of thesystem 10. The sensing device 14 may be configured to transmit sensordata or monitor data to the delivery device 12. The sensing device 14may also be configured to communicate with the CCD 16. The deliverydevice 12 may include electronics and software that are configured toanalyze sensor data and to deliver fluidic media to the body 5 of theuser 7 based on the sensor data and/or preprogrammed delivery routines.

The CCD 16 and the computer 18 may include electronics and othercomponents configured to perform processing, delivery routine storage,and to control the delivery device 12. By including control functions inthe CCD 16 and/or the computer 18, the delivery device 12 may be madewith more simplified electronics. However, in some embodiments, thedelivery device 12 may include all control functions, and may operatewithout the CCD 16 and the computer 18. In various embodiments, the CCD16 may be a portable electronic device. Also, in various embodiments,the delivery device 12 and/or the sensing device 14 may be configured totransmit data to the CCD 16 and/or the computer 18 for display orprocessing of the data by the CCD 16 and/or the computer 18. Examples ofthe types of communications and/or control capabilities, as well asdevice feature sets and/or program options may be found in the followingreferences: (i) U.S. patent application Ser. No. 10/445,477, filed May27, 2003, entitled “External Infusion Device with Remote Programming,Bolus Estimator and/or Vibration Alarm Capabilities”; (ii) U.S. patentapplication Ser. No. 10/429,385, filed May 5, 2003, entitled “HandheldPersonal Data Assistant (PDA) with a Medical Device and Method of Usingthe Same”; and (iii) U.S. patent application Ser. No. 09/813,660, filedMar. 21, 2001, entitled “Control Tabs for Infusion Devices and Methodsof Using the Same”, all of which are incorporated herein by reference intheir entirety.

FIG. 2 illustrates an example of the system 10 in accordance with anembodiment of the present invention. The system 10 in accordance withthe embodiment illustrated in FIG. 2 includes the delivery device 12 andthe sensing device 14. The delivery device 12 in accordance with anembodiment of the present invention includes a disposable housing 20, adurable housing 30, and a reservoir 40. The delivery device 12 mayfurther include an infusion path 50.

Elements of the delivery device 12 that ordinarily contact the body of auser or that ordinarily contact fluidic media during operation of thedelivery device 12 may be considered as a disposable portion of thedelivery device 12. For example, a disposable portion of the deliverydevice 12 may include the disposable housing 20 and the reservoir 40.The disposable portion of the delivery device 12 may be recommended fordisposal after a specified number of uses.

On the other hand, elements of the delivery device 12 that do notordinarily contact the body of the user or fluidic media duringoperation of the delivery device 12 may be considered as a durableportion of the delivery device 12. For example, a durable portion of thedelivery device 12 may include the durable housing 30, electronics (notshown in FIG. 2), a drive device having a motor and drive linkage (notshown in FIG. 2), and the like. Elements of the durable housing portionof the delivery device 12 are typically not contaminated from contactwith the user or fluidic media during normal operation of the deliverydevice 12 and, thus, may be retained for re-use with replaced disposableportions of the delivery device 12.

In various embodiments, the disposable housing 20 supports the reservoir40 and has a bottom surface (facing downward and into the page in FIG.2) that is configured to secure to the body of a user. An adhesive maybe employed at an interface between the bottom surface of the disposablehousing 20 and the skin of a user, so as to adhere the disposablehousing 20 to the skin of the user. In various embodiments, the adhesivemay be provided on the bottom surface of the disposable housing 20, witha peelable cover layer covering the adhesive material. In this manner,the cover layer may be peeled off to expose the adhesive material, andthe adhesive side of the disposable housing 20 may be placed against theskin of the user.

The reservoir 40 is configured for containing or holding fluidic media,such as, but not limited to insulin. In various embodiments, thereservoir 40 includes a hollow interior volume for receiving fluidicmedia, such as, but not limited to, a cylinder-shaped volume, atubular-shaped volume, or the like. In some embodiments, the reservoir40 may be provided as a cartridge or canister for containing fluidicmedia. In various embodiments, the reservoir 40 is able to be refilledwith fluidic media. In further embodiments, the reservoir 40 ispre-filled with fluidic media.

The reservoir 40 may be supported by the disposable housing 20 in anysuitable manner. For example, the disposable housing 20 may be providedwith projections or struts (not shown), or a trough feature (not shown),for holding the reservoir 40. In some embodiments, the reservoir 40 maybe supported by the disposable housing 20 in a manner that allows thereservoir 40 to be removed from the disposable housing 20 and replacedwith another reservoir. Alternatively, or in addition, the reservoir 40may be secured to the disposable housing 20 by a suitable adhesive, astrap, or other coupling structure.

In various embodiments, the reservoir 40 includes a port 41 for allowingfluidic media to flow into and/or flow out of the interior volume of thereservoir 40. In some embodiments, the infusion path 50 includes aconnector 56, a tube 54, and a needle apparatus 52. The connector 56 ofthe infusion path 50 may be connectable to the port 41 of the reservoir40. In various embodiments, the disposable housing 20 is configured withan opening near the port 41 of the reservoir 40 for allowing theconnector 56 of the infusion path 50 to be selectively connected to anddisconnected from the port 41 of the reservoir 40.

In various embodiments, the port 41 of the reservoir 40 is covered withor supports a septum (not shown in FIG. 2), such as a self-sealingseptum, or the like. The septum may be configured to prevent fluidicmedia from flowing out of the reservoir 40 through the port 41 when theseptum is not pierced. Also, in various embodiments, the connector 56 ofthe infusion path 50 includes a needle for piercing the septum coveringthe port 41 of the reservoir 40 so as to allow fluidic media to flow outof the interior volume of the reservoir 40. Examples of needle/septumconnectors can be found in U.S. patent application Ser. No. 10/328,393,filed Dec. 22, 2003, entitled “Reservoir Connector”, which isincorporated herein by reference in its entirety. In other alternatives,non-septum connectors such as Luer locks, or the like may be used. Invarious embodiments, the needle apparatus 52 of the infusion path 50includes a needle that is able to puncture the skin of a user. Also, invarious embodiments, the tube 54 connects the connector 56 with theneedle apparatus 52 and is hollow, such that the infusion path 50 isable to provide a path to allow for the delivery of fluidic media fromthe reservoir 40 to the body of a user.

The durable housing 30 of the delivery device 12 in accordance withvarious embodiments of the present invention includes a housing shellconfigured to mate with and secure to the disposable housing 20. Thedurable housing 30 and the disposable housing 20 may be provided withcorrespondingly shaped grooves, notches, tabs, or other suitablefeatures, that allow the two parts to easily connect together, bymanually pressing the two housings together, by twist or threadedconnection, or other suitable manner of connecting the parts that iswell known in the mechanical arts. In various embodiments, the durablehousing 30 and the disposable housing 20 may be connected to each otherusing a twist action. The durable housing 30 and the disposable housing20 may be configured to be separable from each other when a sufficientforce is applied to disconnect the two housings from each other. Forexample, in some embodiments the disposable housing 20 and the durablehousing 30 may be snapped together by friction fitting. In variousembodiments, a suitable seal, such as an o-ring seal, may be placedalong a peripheral edge of the durable housing 30 and/or the disposablehousing 20, so as to provide a seal against water entering between thedurable housing 30 and the disposable housing 20.

The durable housing 30 of the delivery device 12 may support a drivedevice (not shown in FIG. 2), including a motor and a drive devicelinkage portion, for applying a force to fluidic media within thereservoir 40 to force fluidic media out of the reservoir 40 and into aninfusion path, such as the infusion path 50, for delivery to a user. Forexample, in some embodiments, an electrically driven motor may bemounted within the durable housing 30 with appropriate linkage foroperatively coupling the motor to a plunger arm (not shown in FIG. 2)connected to a plunger head (not shown in FIG. 2) that is within thereservoir 40 and to drive the plunger head in a direction to forcefluidic media out of the port 41 of the reservoir 40 and to the user.Also, in some embodiments, the motor may be controllable to reversedirection so as to move the plunger arm and the plunger head to causefluid to be drawn into the reservoir 40 from a patient. The motor may bearranged within the durable housing 30 and the reservoir 40 may becorrespondingly arranged on the disposable housing 20, such that theoperable engagement of the motor with the plunger head, through theappropriate linkage, occurs automatically upon the user connecting thedurable housing 30 with the disposable housing 20 of the delivery device12. Further examples of linkage and control structures may be found inU.S. patent application Ser. No. 09/813,660, filed Mar. 21, 2001,entitled “Control Tabs for Infusion Devices and Methods of Using theSame”, which is incorporated herein by reference in its entirety.

In various embodiments, the durable housing 30 and the disposablehousing 20 may be made of suitably rigid materials that maintain theirshape, yet provide sufficient flexibility and resilience to effectivelyconnect together and disconnect, as described above. The material of thedisposable housing 20 may be selected for suitable compatibility withskin. For example, the disposable housing 20 and the durable housing 30of the delivery device 12 may be made of any suitable plastic, metal,composite material, or the like. The disposable housing 20 may be madeof the same type of material or a different material relative to thedurable housing 30. In some embodiments, the disposable housing 20 andthe durable housing 30 may be manufactured by injection molding or othermolding processes, machining processes, or combinations thereof.

For example, the disposable housing 20 may be made of a relativelyflexible material, such as a flexible silicone, plastic, rubber,synthetic rubber, or the like. By forming the disposable housing 20 of amaterial capable of flexing with the skin of a user, a greater level ofuser comfort may be achieved when the disposable housing 20 is securedto the skin of the user. Also, a flexible disposable housing 20 mayresult in an increase in site options on the body of the user at whichthe disposable housing 20 may be secured.

In the embodiment illustrated in FIG. 2, the delivery device 12 isconnected to the sensing device 14 through a connection element 16 ofthe sensing device 14. The sensing device 14 may include a sensor 15that includes any suitable biological or environmental sensing device,depending upon a nature of a treatment to be administered by thedelivery device 12. For example, in the context of delivering insulin toa diabetes patient, the sensor 15 may include a blood glucose sensor, orthe like.

The sensor 15 may be an external sensor that secures to the skin of auser or, in other embodiments, may be an implantable sensor that islocated in an implant site within the body of the user. In furtheralternatives, the sensor may be included with as a part or along sidethe infusion cannula and/or needle, such as for example as shown in U.S.patent application Ser. No. 11/149,119, filed Jun. 8, 2005, entitled“Dual Insertion Set”, which is incorporated herein by reference in itsentirety. In the illustrated example of FIG. 2, the sensor 15 is anexternal sensor having a disposable needle pad that includes a needlefor piercing the skin of the user and enzymes and/or electronicsreactive to a biological condition, such as blood glucose level or thelike, of the user. In this manner, the delivery device 12 may beprovided with sensor data from the sensor 15 secured to the user at asite remote from the location at which the delivery device 12 is securedto the user.

While the embodiment shown in FIG. 2 includes a sensor 15 connected bythe connection element 16 for providing sensor data to sensorelectronics (not shown in FIG. 2) located within the durable housing 30of the delivery device 12, other embodiments may employ a sensor 15located within the delivery device 12. Yet other embodiments may employa sensor 15 having a transmitter for communicating sensor data by awireless communication link with receiver electronics (not shown in FIG.2) located within the durable housing 30 of the delivery device 12. Invarious embodiments, a wireless connection between the sensor 15 and thereceiver electronics within the durable housing 30 of the deliverydevice 12 may include a radio frequency (RF) connection, an opticalconnection, or another suitable wireless communication link. Furtherembodiments need not employ the sensing device 14 and, instead, mayprovide fluidic media delivery functions without the use of sensor data.

As described above, by separating disposable elements of the deliverydevice 12 from durable elements, the disposable elements may be arrangedon the disposable housing 20, while durable elements may be arrangedwithin a separable durable housing 30. In this regard, after aprescribed number of uses of the delivery device 12, the disposablehousing 20 may be separated from the durable housing 30, so that thedisposable housing 20 may be disposed of in a proper manner. The durablehousing 30 may then be mated with a new (un-used) disposable housing 20for further delivery operation with a user.

FIG. 3 illustrates an example of the delivery device 12 in accordancewith another embodiment of the present invention. The delivery device 12of the embodiment of FIG. 3 is similar to the delivery device 12 of theembodiment of FIG. 2. While the delivery device 12 in the embodimentillustrated in FIG. 2 provides for the durable housing 30 to cover thereservoir 40, the delivery device 12 in the embodiment of FIG. 3provides for the durable housing 30 to secure to the disposable housing20 without covering the reservoir 40. The delivery device 12 of theembodiment illustrated in FIG. 3 includes the disposable housing 20, andthe disposable housing 20 in accordance with the embodiment illustratedin FIG. 3 includes a base 21 and a reservoir retaining portion 24. Inone embodiment, the base 21 and reservoir retaining portion 24 may beformed as a single, unitary structure.

The base 21 of the disposable housing 20 is configured to be secured tothe body of a user. The reservoir retaining portion 24 of the disposablehousing 20 is configured to house the reservoir 40. The reservoirretaining portion 24 of the disposable housing 20 may be configured tohave an opening to allow for the port 41 of the reservoir 40 to beaccessed from outside of the reservoir retaining portion 24 while thereservoir 40 is housed in the reservoir retaining portion 24. Thedurable housing 30 may be configured to be attachable to and detachablefrom the base 21 of the disposable housing 20. The delivery device 12 inthe embodiment illustrated in FIG. 3 includes a plunger arm 60 that isconnected to or that is connectable to a plunger head (not shown in FIG.3) within the reservoir 40.

FIG. 4 illustrates another view of the delivery device 12 of theembodiment of FIG. 3. The delivery device 12 of the embodimentillustrated in FIG. 4 includes the disposable housing 20, the durablehousing 30, and the infusion path 50. The disposable housing 20 in theembodiment of FIG. 4 includes the base 21, the reservoir retainingportion 24, and a peelable cover layer 25. The peelable cover layer 25may cover an adhesive material on the bottom surface 22 of the base 21.The peelable cover layer 25 may be configured to be peelable by a userto expose the adhesive material on the bottom surface 22 of the base 21.In some embodiments, there may be multiple adhesive layers on the bottomsurface 22 of the base 21 that are separated by peelable layers.

The infusion path 50 in accordance with the embodiment of the presentinvention illustrated in FIG. 4 includes the needle 58 rather than theconnector 56, the tube 54, and the needle apparatus 52 as shown in theembodiment of FIG. 2. The base 21 of the disposable housing 20 may beprovided with an opening or pierceable wall in alignment with a tip ofthe needle 58, to allow the needle 58 to pass through the base 21 andinto the skin of a user under the base 21, when extended. In thismanner, the needle 58 may be used to pierce the skin of the user anddeliver fluidic media to the user.

Alternatively, the needle 58 may be extended through a hollow cannula(not shown in FIG. 4), such that upon piercing the skin of the user withthe needle 58, an end of the hollow cannula is guided through the skinof the user by the needle 58. Thereafter, the needle 58 may be removed,leaving the hollow cannula in place, with one end of the cannula locatedwithin the body of the user and the other end of the cannula in fluidflow connection with fluidic media within the reservoir 40, to conveypumped infusion media from the reservoir 40 to the body of the user.

FIG. 5A illustrates a durable portion 8 of the delivery device 12 (referto FIG. 3) in accordance with an embodiment of the present invention.FIG. 5B illustrates a section view of the durable portion 8 inaccordance with an embodiment of the present invention. FIG. 5Cillustrates another section view of the durable portion 8 in accordancewith an embodiment of the present invention. With reference to FIGS. 5A,5B, and 5C, in various embodiments, the durable portion 8 includes thedurable housing 30, and a drive device 80. The drive device 80 includesa motor 84 and a drive device linkage portion 82. In variousembodiments, the durable housing 30 may include an interior volume forhousing the motor 84, the drive device linkage portion 82, otherelectronic circuitry, and a power source (not shown in FIGS. 5A, 5B, and5C). Also, in various embodiments, the durable housing 30 is configuredwith an opening 32 for receiving a plunger arm 60 (refer to FIG. 3).Also, in various embodiments, the durable housing 30 may include one ormore connection members 34, such as tabs, insertion holes, or the like,for connecting with the base 21 of the disposable housing 20 (refer toFIG. 3).

FIG. 6A illustrates a disposable portion 9 of the delivery device 12(refer to FIG. 3) in accordance with an embodiment of the presentinvention. FIG. 6B illustrates a section view of the disposable portion9 in accordance with an embodiment of the present invention. FIG. 6Cillustrates another section view of the disposable portion 9 inaccordance with an embodiment of the present invention. With referenceto FIGS. 6A, 6B, and 6C, in various embodiments, the disposable portion9 includes the disposable housing 20, the reservoir 40, the plunger arm60, and a plunger head 70. In some embodiments, the disposable housing20 includes the base 21 and the reservoir retaining portion 24. Invarious embodiments, the base 21 includes a top surface 23 having one ormore connection members 26, such as tabs, grooves, or the like, forallowing connections with the one or more connection members 34 ofembodiments of the durable housing 30 (refer to FIG. 5B).

In various embodiments, the reservoir 40 is housed within the reservoirretaining portion 24 of the disposable housing 20, and the reservoir 40is configured to hold fluidic media. Also, in various embodiments, theplunger head 70 is disposed at least partially within the reservoir 40and is moveable within the reservoir 40 to allow fluidic media to fillinto the reservoir 40 and to force fluidic media out of the reservoir40. In some embodiments, the plunger arm 60 is connected to or isconnectable to the plunger head 70. Also, in some embodiments, a portionof the plunger arm 60 extends to outside of the reservoir retainingportion 24 of the disposable housing 20. In various embodiments, theplunger arm 60 has a mating portion for mating with the drive devicelinkage portion 82 of the drive device 80 (refer to FIG. 5C). Withreference to FIGS. 5C and 6C, in some embodiments, the durable housing30 may be snap fitted onto the disposable housing 20, whereupon thedrive device linkage portion 82 automatically engages the mating portionof the plunger arm 60.

When the durable housing 30 and the disposable housing 20 are fittedtogether with the drive device linkage portion 82 engaging or matingwith the plunger arm 60, the motor 84 may be controlled to drive thedrive device linkage portion 82 and, thus, move the plunger arm 60 tocause the plunger head 70 to move within the reservoir 40. When theinterior volume of the reservoir 40 is filled with fluidic media and aninfusion path is provided from the reservoir 40 to the body of a user,the plunger head 70 may be moved within the reservoir 40 to forcefluidic media from the reservoir 40 and into the infusion path, so as todeliver fluidic media to the body of the user.

In various embodiments, once the reservoir 40 has been sufficientlyemptied or otherwise requires replacement, a user may simply remove thedurable housing 30 from the disposable housing 20, and replace thedisposable portion 9, including the reservoir 40, with a new disposableportion having a new reservoir. The durable housing 30 may be connectedto the new disposable housing of the new disposable portion, and thedelivery device including the new disposable portion may be secured tothe skin of a user. In various other embodiments, rather than replacingthe entire disposable portion 9 every time the reservoir 40 is emptied,the reservoir 40 may be refilled with fluidic media. In someembodiments, the reservoir 40 may be refilled while remaining within thereservoir retaining portion 24 (refer to FIG. 6B) of the disposablehousing 20. Also, in various embodiments, the reservoir 40 may bereplaced with a new reservoir (not shown), while the disposable housing20 may be re-used with the new reservoir. In such embodiments, the newreservoir may be inserted into the disposable portion 9.

With reference to FIGS. 3, 5A, 6B, and 6C, in various embodiments, thedelivery device 12 includes reservoir status circuitry (not shown), andthe reservoir 40 includes reservoir circuitry (not shown). In variousembodiments, the reservoir circuitry stores information such as, but notlimited to, at least one of (i) an identification string identifying thereservoir 40; (ii) a manufacturer of the reservoir 40; (iii) contents ofthe reservoir 40; and (iv) an amount of contents in the reservoir 40. Insome embodiments, the delivery device 12 includes the reservoir statuscircuitry (not shown), and the reservoir status circuitry is configuredto read data from the reservoir circuitry when the reservoir 40 isinserted into the disposable portion 9.

In various embodiments, the reservoir status circuitry is furtherconfigured to store data to the reservoir circuitry after at least someof the contents of the reservoir 40 have been transferred out of thereservoir 40, so as to update information in the reservoir circuitryrelated to an amount of contents still remaining in the reservoir 40. Insome embodiments, the reservoir status circuitry is configured to storedata to the reservoir circuitry, so as to update information in thereservoir circuitry related to an amount of contents still remaining inthe reservoir 40, when the reservoir 40 is inserted into the disposableportion 9. In some embodiments, the delivery device 12 includes thereservoir status circuitry (not shown) and the reservoir 40 includes thereservoir circuitry (not shown), and the reservoir status circuitryselectively inhibits use of the delivery device 12 or selectivelyprovides a warning signal based on information read by the reservoirstatus circuitry from the reservoir circuitry.

FIG. 7A illustrates a cross-sectional view of a delivery device 100 inaccordance with an embodiment of the present invention. The deliverydevice 100 may include, but not limited to, a reservoir assembly 102 anda base assembly 104. The reservoir assembly 102 and the base assembly104 may be configured to be connected to and disconnected from oneanother by the user. The base assembly 104, which may be adapted to becarried by the user, may include a fluid path 190 for receiving fluidicmedia from the reservoir assembly 102. The base assembly 104 may alsoinclude a subcutaneous cannula 194 or catheter having a needle path 192to allow an injection needle (not shown) to pierce the skin of the userand allow fluidic media to flow into the body of a patient.

FIG. 7B illustrates a cross-sectional view of the reservoir assembly 102in accordance with an embodiment of the present invention. Withreference to FIGS. 7A and 7B, the reservoir assembly 102 may include areservoir 110 and a first structure 170 having a chamber 175. Thereservoir 110 may contain fluidic media, such as, but not limited to,insulin or the like. The first structure 170 may include a needle 130and a pierceable member 140. The needle 130 may be connected to thereservoir 110 for allowing fluidic media contained in the reservoir 110to flow through the needle 130 when the needle 130 is connected to thereservoir 110. The needle 130 may have a longitudinal dimension and acentral axis along the longitudinal dimension of the needle 130.

The pierceable member 140 may be located within the chamber 175. Thepierceable member 140 may be moveable within the chamber 175 along thelongitudinal dimension of the needle 130. The pierceable member 140 mayhave an interior volume 172 for containing fluidic media expelled fromthe reservoir 110 before the pierceable member 140 is pierced by theneedle 130. In some embodiments of the present invention, the interiorvolume 172 of the pierceable member 140 may be for containing fluidicmedia that flows through the needle 130 from the reservoir 110 beforethe pierceable member 140 is pierced by the needle 130.

In some embodiments of the present invention, the pierceable member 140may have a cross-section that is U-shaped. In some embodiments of thepresent invention, the pierceable member 140 may be made of a resealablematerial. Thus when the user disconnects the reservoir assembly 102 fromthe base assembly 104, for example to replace an empty reservoir with anew reservoir, the needle 130 is retracted or otherwise removed from thepierceable member 140 and the pierceable member 140 is resealed. As aresult, fluidic media contained in the interior volume 172 of thepierceable member 140 may continue to be contained within the interiorvolume 172 of the pierceable member 140. Once the new reservoir isinstalled, the interior volume 172 of the pierceable member 140 may beused to contain fluidic media expelled from the new reservoir before theneedle 130 again pierces the pierceable member 140.

Fluidic media may be expelled from the reservoir 110 before thepierceable member 140 is pierced by the needle 130 when a pressuredifference exists between the reservoir 110 and the chamber 175. Thismay be due to an external influence such as an altitude or a temperaturechange or imperfect alignment of a plunger shaft 725 (refer to FIG. 13)and a driveshaft 772 (refer to FIG. 13). In such a case, fluidic mediamay flow or bolus from the reservoir 110 into the interior volume 172 ofthe pierceable member 140 until pressure in the reservoir 110 has beensufficiently equalized relative to pressure in the chamber 175. Thus,preventing the user from inadvertently being administered fluidic media,which could harm the user. Once pressure has been sufficientlyequalized, fluidic media may be inhibited from flowing through theneedle 130 until directed by the delivery device, for example, tosatisfy the need of the user. In some embodiments, fluidic media may beexpelled from the reservoir 110 before the pierceable member 140 ispierced by the needle 130 in a case where a pressure difference existsbetween the reservoir 110 and the interior volume 172 of the pierceablemember 140.

The pierceable member 140 may have a first end 141 and a second end 142on an opposite side of the pierceable member 140 from the first end 141.The pierceable member 140 may be positioned in the chamber 175 relativeto the needle 130 so that the needle 130 can pierce the pierceablemember 140 when the user connects the reservoir assembly 102 with thebase assembly 104. Connecting the reservoir assembly 102 with the baseassembly 104 may cause the base assembly 104 to push against the firstend 141 of the pierceable member 140. As a result, the pierceable member140 is pushed against the needle 130 causing the needle 130 to piercethrough the pierceable member 140. The needle 130 may be positioned topierce through the pierceable member 140 and enter the fluid path 190 ofthe base assembly 104 when the user connects the reservoir assembly 102with the base assembly 104. In some embodiments, an end of the needle130 may be located at least substantially within the interior volume 172of the pierceable member 140 before the needle 130 pierces thepierceable member 140. This may help ensure that fluidic media thatflows through the needle 130 before piercing the pierceable member 140is collected in the interior volume 172 of the pierceable member 140.

In some embodiments of the present invention, the chamber 175 mayinclude a first chamber 174. The first chamber 174 may be adjacent tothe second end 142 of the pierceable member 140. In other embodiments ofthe present invention, the first chamber 174 may be located between thepierceable member 140 and the reservoir 110. The first chamber 174 maycontain fluidic media that flows out, or otherwise escapes, from theinterior volume 172 of the pierceable member 140. For example, thiscould occur in a case where a volume of fluidic media expelled from thereservoir 110 exceeds a capacity of the interior volume 172 of thepierceable member 140. The excess fluidic media could then flow into thefirst chamber 174 and be contained therein. As a further example,fluidic media could escape from the interior volume 172 of thepierceable member 140 in a case where fluidic media enters the interiorvolume 172 too quickly causing fluidic media to flow out of the interiorvolume 172 into the first chamber 174.

In further embodiments of the present invention, the chamber 175 mayinclude a second chamber 176. The second chamber 176 may be located onan opposite side of the pierceable member 140 from the first chamber174, such as adjacent to the first end 141 of the pierceable member 140.The pierceable member 140 may be located between the first chamber 174and the second chamber 176. The second chamber 176 may contain fluidicmedia that flows out, or otherwise escapes, from the first chamber 174.For example, this could occur in a case where the first chamber 174fills with fluidic media. The excess fluidic media could then flowbetween the pierceable member 140 and the structure 170 into the secondchamber 176. As a further example, fluidic media could escape from thefirst chamber 174 in a case where fluidic media enters the first chamber174 too quickly causing fluidic media to flow out of the first chamber174 into the second chamber 176. In yet further embodiments of thepresent invention, the pierceable member 140 may include a seal member144 around the pierceable member 140. The seal member 144, for example,may aid in inhibiting fluidic media in the second chamber 176 fromflowing back into the first chamber 174. In some embodiments, the sealmember 144 may be an annular ring that encircles the pierceable member140.

In yet further embodiments of the present invention, the structure 170may include an opening 171 in flow communication with the chamber 175.The opening 171 may be for purging fluidic media that flows out, orotherwise escapes, from the interior volume 172 of the pierceable member140. For example, this could occur in a case where a volume of fluidicmedia expelled from the reservoir 110 exceeds the capacity of theinterior volume 172 of the pierceable member 140. The excess fluidicmedia may then flow into the chamber 175 and flow out the opening 171 ofthe structure 170.

In some embodiments of the present invention, the pierceable member 160may include a membrane wall 152, which may comprise an elastomericmaterial, or the like. The membrane wall 152 may be configured to expand152′ to increase the volume of the interior volume 172 of the pierceablemember 140 in a case where the interior volume 172 of the pierceablemember 140 sufficiently fills with fluidic media. This may be useful ina case where the interior volume 172 of the pierceable member 140 is notsufficiently large enough to contain fluidic media expelled from thereservoir 110. The membrane wall 152 may be for inhibiting fluidic mediacontained in the interior volume 172 of the pierceable member 140 fromflowing out of or otherwise escaping from the interior volume 172 of thepierceable member 140. The membrane wall 152 may also be configured toallow for pressure equalization across it through the use of ahydrophobic or hydrophilic filter or similar material.

With reference to FIGS. 7B and 7C, in some embodiments of the presentinvention, the reservoir assembly 102 may include a bias member 160. Thebias member 160 may be arranged to impart a bias force on the pierceablemember 140 as, for instance, the base assembly 104 is pushed against thefirst end 141 of the pierceable member 140 when the user connects thereservoir assembly 102 with the base assembly 104. As a result, thepierceable member 140 can be moved from a first position 191 to a secondposition 191′. Additionally, the pierceable member 140 may be moved tovarious positions between the first position 191 and the second position191′, as well as positions beyond the second position 191′. In someembodiments of the present invention, the bias member 160 may be, but isnot limited to, a spring or the like.

In further embodiments of the present invention, the pierceable member140 may have a resiliently flexible portion (not shown) for providing abias force on the pierceable member 140. In various embodiments, thebias function may be integral to the pierceable member 140, a functionof the resiliently flexible portion (not shown), which may be made of amaterial such as rubber, or the like. The flexible portion (not shown)may, for example, compress allowing the pierceable member 140 to movewithin the chamber 175 from the first position 191 to the secondposition 191′ when the user connects the base assembly 104 with thereservoir assembly 102 and uncompress when the user disconnects the baseassembly 104 and the reservoir assembly 102 returning the pierceablemember 140 to the first position 191.

In alternative embodiments, the needle 130 may be supported by the baseassembly 104 and positioned to pierce the pierceable member 140 andenter the reservoir 110. The interior volume 172 of the pierceablemember 140 may contain fluidic media expelled from the reservoir 110before the pierceable member 140 is pierced by the needle 130.

In some embodiments of the present invention, the interior volume 172 ofthe pierceable member 140 may be curved concavely relative to thecentral axis of the needle 130. This may increase the capacity of theinterior volume 172 of the pierceable member 140 to hold more fluidicmedia. Furthermore, this may allow more fluidic media to be containedwithin the interior volume 172 of the pierceable member 140 when thereservoir assembly 102 is orientated on its side, for example, when thecentral axis of the needle 130 is parallel to an infusion site (notshown) as may be a case in FIGS. 7A-7C. In further embodiments of thepresent invention, the system 100 may include a seal member, such as ano-ring 150 or the like located between the structure 170 and thepierceable member 140 to facilitate movement of the pierceable member140 within the chamber 175. In some embodiments, the o-ring 150 maysubstantially prevent fluidic media from flowing between the pierceablemember 140 and the structure 170.

FIG. 7C illustrates a cross-sectional view of the reservoir assembly 102connected to the base assembly 104 in accordance with an embodiment ofthe present invention. Once pressure in the reservoir 110 has beensufficiently equalized, the user may connect the reservoir assembly 102with the base assembly 104. When the user connects the reservoirassembly 102 and the base assembly 104, the base assembly 104 is pushedagainst the first end 141 of the pierceable member 140. This forces thepierceable member 140 against the bias member 160 and moves thepierceable member 140 from the first position 191 (refer to FIG. 7B) tothe second position 191′ causing the needle 130 to pierce through thepierceable member 140 and enter the fluid path 190 of the base assembly104. As a result, fluidic media can flow from the reservoir 110 throughthe needle 130 into the fluid path 190 and into the user by way of theneedle path 192 and cannula 194 (refer to FIG. 7A) as required by theuser.

Fluidic media expelled from the reservoir 110 and collected in theinterior volume 172 of the pierceable member 140 before the needle 130pierces the pierceable member 140 may remain in the interior volume 172of the pierceable member 140. In other embodiments, fluidic mediaexpelled from the reservoir 110 before the needle 130 pierces thepierceable member 140 may remain in at least one of the interior volume172 of the pierceable member 140, the first chamber 174, or the secondchamber 176.

FIG. 8A illustrates a cross-sectional view of a system 200 forequalizing pressure in a first position in accordance with an embodimentof the present invention. The system 200 may include, but is not limitedto, a reservoir assembly 202 and a base assembly 204. The reservoirassembly 202 may include a reservoir 210 having a port 212 and a septum214, a plug 240, and a structure 255 having a chamber 250. The baseassembly 204, which may be adapted to be carried by the user, mayinclude a needle 230. The needle 230 may be for piercing the septum 214of the reservoir 210 when the user connects the base assembly 204 withthe reservoir assembly 202. The needle 230 may be for allowing fluidicmedia contained in the reservoir 210 to flow through the needle 230 intothe base assembly 204 when the needle 230 is connected to the reservoir210 when, for example, the needle 230 pierces the septum 214 and entersthe reservoir 210.

The reservoir 210 may have an interior volume 215 for containing fluidicmedia, such as, but not limited to, insulin. The port 212 of thereservoir 210 may be for allowing fluidic media to be expelled from thereservoir 210 in a case where a pressure difference exists between theinterior volume 215 of the reservoir 210 and the chamber 250. Asdiscussed, this could be due, but is not limited to, an externalinfluence such as an altitude or a temperature change or imperfectalignment of a plunger shaft 225 and a driveshaft 272 when the reservoir210 is installed into the delivery device.

The plug 240 may be positioned relatively offset to the port 212 of thereservoir 210. The plug 240 may be for closing the port 212 of thereservoir 210 when the plug 240 is in a closed position. For example,when the user connects the reservoir assembly 202 and the base assemblytogether 204, the base assembly 204 forces the plug 240 into or over theport 212 of the reservoir 210 to close the port 212, thus preventingfluidic media in the interior volume 215 of the reservoir 210 fromflowing out the port 212 of the reservoir 210. The plug 240 may be, butis not limited to, a flapper valve, a disc valve, or the like.

The chamber 250 of the structure 255 may be connected to the reservoir210. The chamber 250 may be for collecting fluidic media expelled fromthe interior volume 215 of the reservoir 210 in a case where a pressuredifference exists between the interior volume 215 of the reservoir 210and the chamber 250. As shown in FIG. 8A, the plug 240 initially may bein an open position so that the port 212 is at least partiallyunobstructed so that fluidic media can flow freely or bolus through theport 212 into the chamber 250 in a case where a pressure differenceexists between the interior volume 215 of the reservoir 210 and thechamber 250. Fluidic media may flow through the port 212 until pressurewithin the interior volume 215 of the reservoir 210 has beensufficiently equalized relative to pressure in the chamber 250. In otherembodiments, the plug 240 may be located at least partially in or overthe port 212 and may be positioned to be forced away from the port 212by the expelled fluidic media. Once pressure in the interior volume 215of the reservoir 210 has been sufficiently equalized, the reservoirassembly 202 may be connected with the base assembly 204.

The structure 255 having the chamber 250 may be located outside of thereservoir 210. For example, the chamber 250 may be adjacent to thereservoir 210. In other embodiments, such as the embodiment illustratedin FIG. 8C, a structure 256 having a chamber 251 may be located withinthe reservoir 210. With reference to FIG. 8A, in further embodiments ofthe present invention, the structure 255 may include a membrane wall252, which may comprise an elastomeric material, or the like. Themembrane wall 252 may also be configured to allow for pressureequalization across it through the use of a hydrophobic or hydrophilicfilter or similar material. The membrane wall 252 may be configured toexpand (252′ in FIG. 8B) to increase the volume of the chamber 250 in acase where the chamber 250 sufficiently fills with fluidic media. In yetfurther embodiments of the present invention, the structure 255 may havean opening (not shown) in communication with the chamber 250 for purgingfluidic media collected in the interior volume of the chamber 250. Thismay be useful in a case where the interior volume of the chamber 250 isnot sufficiently large enough to contain fluidic media expelled from theinterior volume 215 of the reservoir 210.

FIG. 8B illustrates a cross-sectional view of the system 200 forrelieving pressure in a second position in accordance with an embodimentof the present invention. Once pressure in the interior volume 215 ofthe reservoir 210 has been sufficiently equalized, the user may placethe system 200 in the second position by connecting the reservoirassembly 202 with the base assembly 204. In the second position of thesystem 200, the plug 240 may be in a closed position so that the port212 of the reservoir 210 is substantially closed, such that fluidicmedia in the interior volume 215 of the reservoir 210 can no longer flowinto the chamber 250. The port 212 may be closed by the plug 240 whenthe user connects the reservoir assembly 202 with the base assembly 204.In such a case, the base assembly 204 pushes against the plug 240 of thereservoir assembly 202 and forces the plug 240 to enter, or otherwisecover, the port 212 of the reservoir 210 of the reservoir assembly 202.The plug 240 may be held in or against the port 212 by the base assembly204. The plug 240 may cover the port 212 of the reservoir 210, andfluidic media contained in the chamber 250 may remain isolated fromfluidic media contained in the interior volume 215 of the reservoir 210.In some embodiments of the present invention, the base assembly 204 andthe reservoir assembly 202 are not connected until pressure in theinterior volume 215 of the reservoir 210 has been equalized with respectto pressure in the chamber 250.

According to the embodiment illustrated in FIG. 8B, when the userconnects the reservoir assembly 202 and the base assembly 204 together,the needle 230, which may be supported by the base assembly 204, piercesthe septum 214 of the reservoir 210 and enters the reservoir 210. As aresult, fluidic media contained in the interior volume 215 of thereservoir 210 can flow through the needle 230 into the base assembly 204and ultimately to the user. For example with reference to FIGS. 7A and8B, fluidic media in the interior volume 215 of the reservoir 210 mayflow through the needle 230 into a fluid path 190 into the needlepassage 192 and then the cannula 194 and into the user. In otherembodiments of the present invention, the needle 230 may be positionedto pierce the plug 240 and enter the reservoir 210. Thus establishing apath for fluidic media in the interior volume 215 of the reservoir 210to flow through the needle 230 into the base assembly 204 and then tothe user. In further embodiments, the reservoir 210 may have a secondport (not shown) for delivering fluidic media contained in the interiorvolume 215 of the reservoir 210 to the base assembly 204 while thereservoir assembly 202 and the base assembly 204 are connected.

FIG. 9A illustrates a cross-sectional view of a system 300 forequalizing pressure in accordance with an embodiment of the presentinvention. The system 300 may include, but is not limited to, areservoir 310 and a plunger head 320. The reservoir 310 may have aninterior volume 315 for containing fluidic media, such as, but notlimited to, insulin. The reservoir 310 may have a passage 340 forallowing fluidic media to be expelled from the interior volume 315 ofthe reservoir 310 in a case where a pressure difference exists betweenthe interior volume 315 of the reservoir 310 and the passage 340.

The plunger head 320 may be located within the reservoir 310 and may bemoveable within the reservoir 310 to expand or contract the interiorvolume 315 of the reservoir 310. The plunger head 320 may be connectedto a plunger shaft 325. The plunger shaft 325 may comprise, for example,a half-nut, a quarter-nut, a U-shaped nut, or the like, that is able toengage a driveshaft 372 mechanically coupled to a motor (not shown). Thedriveshaft 372 may be, for example, a partial screw or the like. Theplunger head 320 may have a first surface 321 and a second surface 322connected by a channel 330. The plunger head 320 may be moveable withinthe reservoir 310 to align the channel 330 with the passage 340. Whenthe channel 330 and the passage 340 are aligned and a pressuredifference exists between the interior volume 315 of the reservoir 310and the passage 340, fluidic media may be expelled from the interiorvolume 315 of the reservoir 310 through the passage 340.

In some embodiments of the present invention, the reservoir 310 may havea second interior volume 317. The interior volume 315 of the reservoir310 may allow for containing fluidic media. The plunger head 320 may belocated between the interior volume 315 of the reservoir 310 and thesecond interior volume 317 of the reservoir 310. As the plunger head 320is advanced within the reservoir 310, the interior volume 315 may bedecreased, while the second interior volume 317 may be increased. Thefirst surface 321 of the plunger head 320 may be in contact with fluidicmedia when fluidic media is in the interior volume 315 of the reservoir310.

In some embodiments of the present invention, the first surface 321 ofthe plunger head 320 may be perpendicular to the second surface 322 ofthe plunger head 320. For example, in the embodiment illustrated in FIG.9A, when the channel 330 and the passage 340 are aligned and a pressuredifference exists between the interior volume 315 of the reservoir 310and the passage 340, fluidic media expelled from the interior volume 315of the reservoir 310 may flow into the channel 330 and flow out thepassage 340 located on a side of the reservoir 310. In furtherembodiments of the present invention, the system 300 may include a sealmember (not shown), such as an o-ring or the like, located between theplunger head 320 and the reservoir 310 to facilitate movement of theplunger head 320 within the reservoir 310 and to prevent from fluidicmedia from flowing between the plunger head 320 and the reservoir 310.

The plunger head 320 may be moveable within the reservoir 310 from afirst position 390 to a second position 390′ (refer to FIG. 9B). In someembodiments, when the plunger head 320 is in the first position 390, thechannel 330 and the passage 340 are aligned to establish a flow pathfrom the interior volume 315 of the reservoir 310 through the channel330 of the plunger head 320 to the passage 340 of the reservoir 310. Ina case where the channel 330 and the passage 340 are aligned and apressure difference exists between the interior volume 315 of thereservoir 310 and the passage 340, fluidic media in the interior volume315 of the reservoir 310 can flow freely or bolus through the channel330 into the passage 340 until pressure in the interior volume 315 ofthe reservoir 310 is sufficiently equalized with respect to pressure inthe passage 340. In the second position 390′ (refer to FIG. 7B), thepassage 340 and the chamber 330 are disaligned (i.e., no longer aligned)so that fluidic media can no longer flow from the interior volume 315 ofthe reservoir 310 through the passage 340.

In some embodiments of the present invention, such as the embodimentshown in FIG. 9D, the system 300 may include a reservoir assembly 302and a base assembly 304. The reservoir assembly 302 may support thereservoir 310. The reservoir assembly 302 can be removably attachable tothe base assembly 304. With reference to FIGS. 9A and 9B, the plungerhead 320 may be advanceable within the reservoir 310 from the firstposition 390, where the passage 340 and the channel 330 are aligned, tothe second position 390′, where the passage 340 and the channel 330 aredisaligned, before the user connects the base assembly 304 to thereservoir assembly 302. The plunger head 320 may be advanced, forexample, manually by the user, or by a motor (not shown) attached to thedriveshaft 372. In such an embodiment, the reservoir 310, having theplunger head 320 in the second position 390′, would be ready toadminister fluidic media safely to the user as needed. Moreover, becausefluidic media can no longer flow into the passage 340, fluidic media maynot be wasted when the plunger head 320 is advanced from the secondposition 390′ to another position.

In some embodiments of the present invention, the reservoir 310 mayfurther include a structure 355 having a chamber 350. The chamber 350 ofthe structure 355 may be connected to the passage 340. The chamber 350may be for collecting fluidic media that flows through the passage 340.Fluidic media may flow through the passage 340 when the channel 330 andthe passage 340 are aligned and a pressure difference exists between theinterior volume 315 of the reservoir 310 and the passage 340. Thestructure 355 having the chamber 350 may be located outside of thereservoir 310, for example, the chamber 350 may be adjacent to thereservoir 310. In other embodiments of the present invention, such asthe embodiment illustrated in FIG. 9C, a structure 356 having a chamber351 may be located within the reservoir 310.

In further embodiments of the present invention, such as the embodimentsillustrated in FIGS. 9A and 9B, the structure 355 may include a membranewall 352, which may comprise an elastomeric material, or the like. Themembrane wall 352 may be configured to expand 352′ to increase thevolume of the chamber 350 in a case where the chamber 350 sufficientlyfills with fluidic media. This may be useful in a case where the chamber350 is not sufficiently large enough to contain fluidic media expelledfrom the reservoir 310. The membrane wall 352 may also be configured toallow for pressure equalization across it through the use of ahydrophobic or hydrophilic filter or similar material.

In some embodiments of the present invention, a valve 335 may bepositioned at an end of the channel 330. The valve 335 may be, but isnot limited to, a flapper valve or the like. The valve 335 may bemoveable between an open position and a closed position. The valve 335may be for closing the channel 330 when the valve 335 is in the closedposition. The valve 335 may be in the closed position after the plungerhead 320 is advanced from the first position 390 to the second position390′ due to an abutting side 311 of the reservoir 310 that may preventthe valve 335 from opening. As a result, fluidic media in the interiorvolume 315 of the reservoir 310 may be prevented from flowing out thechannel 330. In some embodiments, the valve 335 may be in the closedposition while the plunger head 320 is in the first position 390 in acase where pressure in the interior volume 315 of the reservoir 310 isrelatively equal to pressure in the passage 340, such as after pressurehas been equalized or if pressure did not have to be equalized.

In some embodiments of the present invention, a valve 345 may bepositioned at an end of the passage 340. The valve 345 may be, but notlimited to, a flapper valve or the like. The valve 345 may be moveablebetween an open position and a closed position. The valve 345 may be forclosing the passage 340 when the valve 345 is in the closed position.The valve 345 may be in the closed position after the plunger head 320is advanced from the first position 390 to the second position 390′. Asa result, fluidic media expelled through the passage 340, while theplunger head 320 was in the first position 390, may be prevented fromflowing back into the second interior volume 317 of the reservoir 310.This may be desirable because it may keep the reservoir 310 and thedelivery device relatively clean and sanitary. In some embodiments, thevalve 345 may be in the closed position while the plunger head 320 is inthe first position 390 in a case where pressure in the interior volume315 of the reservoir 310 is relatively equal to pressure in the passage340, such as after pressure has been equalized or if pressure did nothave to be equalized.

FIG. 9B illustrates a cross-sectional view of the system 300 inaccordance with an embodiment of the present invention. Once pressure inthe interior volume 315 of the reservoir 310 has been sufficientlyequalized with respect to pressure in the passage 340, the plunger head320 may be sufficiently advanced within the reservoir 310 from the firstposition 390 (refer to FIG. 9A) to the second position 390′. As aresult, the passage 340 and the channel 330 of the plunger head 320 aredisaligned (i.e., no longer aligned) so that fluidic media in theinterior volume 315 of the reservoir 310 may no longer flow into thepassage 340. Accordingly, fluidic media that flows from the interiorvolume 315 of the reservoir 310 into the channel 330 may be preventedfrom flowing into the passage 340 or otherwise out of the reservoir 310by the abutting side 311 of the reservoir 310. In addition, fluidicmedia expelled through the passage 340 may be isolated from fluidicmedia contained in the interior volume 315 of the reservoir 310. Thereservoir 310 may now be ready to provide fluidic media to the user.

In yet further embodiments, the plunger head 320 need not be advancedfrom the first position 390 (refer to FIG. 9A) to the second position390′ after pressure in the interior volume 315 of the reservoir 310 hasbeen equalized with respect to pressure in the passage 340. In such anembodiment, the reservoir 310 may be ready to provide fluidic media tothe user. For example, when the plunger head 320 is advanced from thefirst position 390 (refer to FIG. 9A) to satisfy a need of the user, theadvancement of the plunger head 320 may be sufficient to disalign thechannel 330 and the passage 340 so that the interior volume 315 of thereservoir 310 is no longer in flow communication with the passage 340.

In some embodiments, such as the embodiment illustrated in FIG. 9D, thebase assembly 304 may include a needle 380 and a mating piece 370. Theneedle 380 may be for piercing a septum 314 of the reservoir 310 whenthe user connects the base assembly 304 with the reservoir assembly 302.The needle 380 may be for allowing fluidic media contained in theinterior volume 315 of the reservoir 310 to flow through the needle 380into the base assembly 304 when the needle 380 is connected to thereservoir 310 when, for example, the needle 380 pierces the septum 314and enters the interior volume 315 of the reservoir 310. The matingpiece 370 may be for covering or blocking the passage 340 when the baseassembly 302 and the reservoir assembly 304 are connected so thatfluidic media in the interior volume 315 of the reservoir 310 cannotflow out the passage 340 while the reservoir assembly 302 and the baseassembly 304 are connected.

FIG. 10A illustrates a cross-sectional view of a system 400 forequalizing pressure in a first position in accordance with an embodimentof the present invention. The system 400 may include, but is not limitedto, a reservoir assembly 402 and a base assembly 404. The reservoirassembly 402 may include a reservoir 410 having a port 412 and a flappervalve 440. The base assembly 404 may include a needle 430 and a matingpiece 435. The reservoir 410 may have an interior volume 415 forcontaining fluidic media, such as, but not limited to, insulin. The port412 may be an outlet for expelling fluidic media from the interiorvolume 415 of the reservoir 410 before the mating piece 435 and thereservoir 410 are operatively engaged. The mating piece 435 and thereservoir 410 may be operatively engaged when the user connects thereservoir assembly 402 with the base assembly 404.

The flapper valve 440 may be located on the port 412 of the reservoir410. The flapper valve 440 may be pierceable by the needle 430. Theneedle 430 may be supported by the mating piece 435 and positioned topierce the flapper valve 440 when the user connects the reservoirassembly 402 with the base assembly 404 allowing the needle 430 to enterthe interior volume 415 of the reservoir 410 to establish a fluid pathbetween the reservoir assembly 402 and the base assembly 404. Theflapper valve 440 may be held against the port 412 by the mating piece435, thus closing the port 412 when the user connects the reservoirassembly 402 with the base assembly 404.

In some embodiments of the present invention, the system 400 may furtherinclude a structure 455 having a chamber 450. The chamber 450 of thestructure 455 may be connected to the port 412 of the reservoir 410. Inother embodiments, the chamber 450 may be connectable to or otherwise inflow communication with the interior volume 415 of the reservoir 410.For example, when the flapper valve 440 is opened to expel fluidicmedia, a fluid path may be established between the interior volume 415of the reservoir 410 and the chamber 450. The chamber 450 may have aninterior volume for collecting fluidic media expelled through the port412 from the interior volume 415 of the reservoir 410 before the matingpiece 435 and the reservoir 410 are connected or otherwise operativelyengaged. Fluidic media may be expelled from the reservoir 410 before themating piece 435 and the reservoir 410 are operatively engaged in a casewhere a pressure difference exists between the interior volume 415 ofthe reservoir 410 and the chamber 450. The structure 455 having thechamber 450 may be located outside of the reservoir 410. For example,the chamber 450 may be adjacent to the reservoir 410. In someembodiments of the present invention, such as the embodiment illustratedin FIG. 10C, a structure 456 having a chamber 451 may be located withinthe reservoir 410.

As shown in FIG. 10A, the port 412 of the reservoir 410 may be initiallyin an open position, such that fluidic media expelled from the reservoir410 to equalize pressure within the interior volume 415 of the reservoir410, can flow freely or bolus through the port 412. The expelled fluidicmedia may force the flapper valve 440 to open and flow out of theinterior volume 415 of the reservoir 410 until pressure within theinterior volume 415 of the reservoir 410 has been equalized with respectto pressure in the chamber 450.

In some embodiments of the present invention, the structure 455 mayinclude a membrane wall 452, which may comprise an elastomeric material,or the like. The membrane wall 452 may be configured to expand (452′ inFIG. 10B) outwardly to increase the interior volume of the chamber 450in a case where the chamber 450 sufficiently fills with fluidic media.The membrane wall 452 may also be configured to allow for pressureequalization across it through the use of a hydrophobic or hydrophilicfilter or similar material. In yet further embodiments of the presentinvention, the structure 455 may have an opening (not shown) for purgingfluidic media collected in the interior volume of the chamber 450. Thismay be useful in a case where the interior volume of the chamber 450 isnot sufficiently large enough to contain all of the fluidic mediaexpelled from the interior volume 415 of the reservoir 410.

FIG. 10B illustrates a cross-sectional view of the system 400 forequalizing pressure in a second position in accordance with anembodiment of the present invention. Once pressure in the interiorvolume 415 of the reservoir 410 has been sufficiently equalized, theuser may connect the reservoir assembly 402 with the base assembly 404.When the user connects the reservoir assembly 402 with the base assembly404, the mating piece 435 may push the flapper valve 440 against theport 412 to close or block the port 412, such that fluidic media in theinterior volume 415 of the reservoir 410 can no longer flow out the port412 to the chamber 450. The needle 430 pierces the flapper valve 440 toallow fluidic media contained in the interior volume 415 of thereservoir 410 to flow through the needle 430 to the base assembly 404and then to the user. For example, fluidic media could flow from theinterior volume 415 of the reservoir 410 through the needle 430 into afluid path (such as 190 in FIG. 7A) in the base assembly 404 and to theuser by way of a cannula (such as 194 in FIG. 7A).

The mating piece 435 may securely hold the flapper valve 440 against theport 412 to prevent the flapper valve 440 from opening while thereservoir assembly 402 and the base assembly 404 are connected. In someembodiments of the present invention, the mating piece 435 may seal offthe chamber 450, thus inhibiting fluidic media contained in the chamber450 from flowing back into the interior volume 415 of the reservoir 410or otherwise flowing out of the chamber 450.

FIG. 11A illustrates a cross-sectional view of a system 500 forequalizing pressure in a first position in accordance with an embodimentof the present invention. The system 500 may include, but is not limitedto, a reservoir assembly 502 and a base assembly 504. The reservoirassembly 502 may include a reservoir 510 having a port 512 and a cap540. The base assembly 504 may include a needle 530 and a mating piece535. The reservoir 510 may have an interior volume 515 for containingfluidic media, such as, but not limited to, insulin. The port 512 may bean outlet for expelling fluidic media from the interior volume 515 ofthe reservoir 510 before the mating piece 535 and the reservoir 510 areoperatively engaged. The mating piece 535 and the reservoir 510 may beoperatively engaged when the user connects the reservoir assembly 502with the base assembly 504.

The cap 540 may be located on the port 512 of the reservoir 510. The cap540 may be loosely fitted on the port 512 to allow fluidic media in thereservoir 510 to push against the cap 540 and lift the cap 540 from theport 512 and flow out the interior volume 515 of the reservoir 510. Inother embodiments, such as the embodiment shown in FIG. 11A, the cap 540may be positioned relatively offset to the port 512 so that fluidicmedia may flow freely through the port 512. The cap 540 may bepierceable by the needle 530. The needle 530 may be supported by themating piece 535 and positioned to pierce the cap 540 when the userconnects the reservoir assembly 502 with the base assembly 504 allowingthe needle 530 to enter the interior volume 515 of the reservoir 510 toestablish a fluid path between the reservoir assembly 502 and the baseassembly 504. The cap 540 may be held against the port 512 by the matingpiece 535, thus closing the port 512 when the user connects thereservoir assembly 502 with the base assembly 504.

In some embodiments of the present invention, the system 500 may furtherinclude a structure 555 having a chamber 550. The chamber 550 of thestructure 555 may be connected to the port 512 of the reservoir 510. Inother embodiments, the chamber 550 may be connectable or otherwise inflow communication with the interior volume 515 of the reservoir 510.For example, when the cap 540 is lifted from the port 512 to allowfluidic media to be expelled from the interior volume 515 of thereservoir 510, a fluid path may be established from the interior volume515 of the reservoir 510 to the chamber 550. The chamber 550 may have aninterior volume for collecting fluidic media expelled through the port512 from the interior volume 515 of the reservoir 510 before the matingpiece 535 and the reservoir 510 are connected or otherwise operativelyengaged. Fluidic media may be expelled from the reservoir 510 before themating piece 535 and the reservoir 510 are operatively engaged in a casewhere a pressure difference exists between the interior volume 515 ofthe reservoir 510 and the chamber 550. The structure 555 having thechamber 550 may be located outside of the reservoir 510, for example,the chamber 550 may be adjacent to the reservoir 510. In otherembodiments of the present invention, the structure 555 having thechamber 550 may be located within the reservoir 510.

As shown in FIG. 11A, the port 512 of the reservoir 510 may be initiallyin an open position, such that fluidic media expelled from the interiorvolume 515 of the reservoir 510 to equalize pressure within the interiorvolume 515 of the reservoir 510, can flow freely or bolus through theport 512 into the chamber 550. In some embodiments, the expelled fluidicmedia may push against the cap 540 to move the cap 540 from the port 512allowing fluidic media to flow out of the interior volume 515 of thereservoir 510 until pressure in the interior volume 515 of the reservoir510 has been equalized with respect to pressure in the chamber 550.

In further embodiments of the present invention, the structure 555 mayinclude a membrane wall 552, which may comprise an elastomeric material,or the like. The membrane wall 552 may be configured to expand (552′ inFIG. 11B) outwardly to increase the interior volume of the chamber 550in a case where the chamber 550 sufficiently fills with fluidic media.The membrane wall 552 may also be configured to allow for pressureequalization across it through the use of a hydrophobic or hydrophilicfilter or similar material. In yet further embodiments of the presentinvention, the structure 555 may have an opening (not shown) for purgingfluidic media collected in the interior volume of the chamber 550.

FIG. 11B illustrates a cross-sectional view of the system 500 forequalizing pressure in a second position in accordance with anembodiment of the present invention. Once pressure in the interiorvolume 515 of the reservoir 510 has been sufficiently equalized, theuser may connect the reservoir assembly 502 with the base assembly 504.When the user connects the reservoir assembly 502 with the base assembly504, the mating piece 535 of the base assembly 504 pushes the cap 540against the port 512 of the reservoir 510 to close or block the port512. Thus, fluidic media in the interior volume 515 of the reservoir 510can no longer flow out the port 512 into the chamber 550. The needle 530pierces the cap 540 to allow fluidic media contained in the interiorvolume 515 of the reservoir 510 to flow through the needle 530 to thebase assembly 504 and then to the user. For example, fluidic media couldflow from the interior volume 515 of the reservoir 510 through theneedle 530 into a fluid path (such as 190 in FIG. 7A) in the baseassembly 504 and to the user by way of a cannula (such as 194 in FIG.7A).

The mating piece 535 may securely hold the cap 540 against the port 512to prevent the cap 540 from opening while the reservoir assembly 502 andthe base assembly 504 are connected. In some embodiments of the presentinvention, the mating piece 535 may block or seal off the chamber 550,thus inhibiting fluidic media contained in the chamber 550 from flowingback into the interior volume 515 of the reservoir 510 or otherwiseflowing out of the chamber 550.

FIG. 12A illustrates a cross-sectional view of a system 600 forequalizing pressure in a first position in accordance with an embodimentof the present invention. The system 600 may include, but is not limitedto, a reservoir assembly 602 and a base assembly 604. The reservoirassembly 602 may include a reservoir 610 having a port 612 and acovering 640 having an opening 642. The base assembly 604 may include aneedle 630 and a mating piece 635. The reservoir 610 may have aninterior volume 615 for containing fluidic media, such as, but notlimited to, insulin. The port 612 may be an outlet for expelling fluidicmedia from the interior volume 615 of the reservoir 610 through theopening 642 in the covering 640 before the mating piece 635 and thereservoir 610 are operatively engaged. Fluidic media may be expelledfrom the interior volume 615 of the reservoir 610 before the matingpiece 635 and the reservoir 610 are operatively engaged, for example, ina case where a pressure difference exists between the interior volume615 of the reservoir 610 and a chamber 650 attached to the port 612. Themating piece 635 and the reservoir 610 may be operatively engaged whenthe user connects the reservoir assembly 602 with the base assembly 604.

The covering 640 may be located on the port 612 of the reservoir 610.The covering 640 may be pierceable by the needle 630. The needle 630 maybe supported by the mating piece 635 and positioned to pierce thecovering 640 and to enter the reservoir 610 when the user connects thereservoir assembly 602 with the base assembly 604. Thus, when thereservoir assembly 602 and the base assembly 604 are connected, a fluidflow path is established between the reservoir assembly 602 and the baseassembly 604. The opening 642 in the covering 640 may be closed orblocked by the mating piece 635 when the user connects the reservoirassembly 602 with the base assembly 604, such that, for example, fluidicmedia can no longer flow out the port 612 into the chamber 650.

In some embodiments of the present invention, the system 600 may furtherinclude a structure 655 having the chamber 650. The chamber of thestructure 650 may be connected to the port 612 of the reservoir 610. Inother embodiments, the chamber 650 may be connectable or otherwise inflow communication with the interior volume 615 of the reservoir 610.For example, fluidic media may be expelled from the interior volume 615of the reservoir 610 through the opening 642 in the covering 640 intothe chamber 650. The chamber 650 may have an interior volume forcollecting fluidic media expelled through the opening 642 from theinterior volume 615 of the reservoir 610 before the mating piece 635 andthe reservoir 610 are connected or otherwise operatively engaged.Fluidic media may be expelled from the interior volume 615 of thereservoir 610 before the mating piece 635 and the reservoir 610 areoperatively engaged in a case where a pressure difference exists betweenthe interior volume 615 of the reservoir 610 and the chamber 650. Thestructure 655 having the chamber 650 may be located outside of thereservoir 610. For example, the chamber 650 may be adjacent to thereservoir 610. In other embodiments of the present invention, such asthe embodiment illustrated in FIG. 12C, a structure 656 having a chamber651 may be located within the reservoir 610.

As shown in FIG. 12A, the port 612 of the reservoir 610 may be initiallyin an open position, such that fluidic media expelled from the interiorvolume 615 of the reservoir 610 to equalize pressure within the interiorvolume 615 of the reservoir 610 can flow freely or bolus through theport 612 and the opening 642 in the covering 640. Fluidic media may flowthrough the port 612 and the opening 642 in the covering 640 untilpressure within the interior volume 615 of the reservoir 610 has beensufficiently equalized with respect to pressure in the chamber 650.

In further embodiments of the present invention, the structure 655 mayinclude a membrane wall 652, which may comprise an elastomeric material,or the like. The membrane wall 652 may be configured to expand (652′ inFIG. 11B) outwardly to increase the interior volume of the chamber 650in a case where the chamber 650 sufficiently fills with fluidic media.The membrane wall 652 may also be configured to allow for pressureequalization across it through the use of a hydrophobic or hydrophilicfilter or similar material. In yet further embodiments of the presentinvention, the structure 655 may have an opening (not shown) for purgingfluidic media collected in the interior volume of the chamber 650. Thismay be useful in a case where the interior volume of the chamber 650 isnot sufficiently large enough to contain all of the fluidic mediaexpelled from the interior volume 615 of the reservoir 610.

In some embodiments of the present invention, the reservoir 610 mayfurther include a valve 645, such as, but not limited to, a flappervalve or the like. The flapper valve 645 may be located on the opening642 of the covering 640. The flapper valve 645 may be forced open whenfluidic media is expelled from the interior volume 615 of the reservoir610 to equalize pressure within the interior volume 615 of the reservoir610 with respect to pressure in the chamber 650. The flapper valve 645may be held against the opening 642 by the mating piece 635 when theuser connects the reservoir assembly 602 with the base assembly 604,thus closing the opening 642 to prevent fluidic media from flowing outthe opening 642 to the chamber 650.

FIG. 12B illustrates a cross-sectional view of the system 600 forequalizing pressure in a second position in accordance with anembodiment of the present invention. Once pressure in the interiorvolume 615 of the reservoir 610 has been sufficiently equalized, theuser may connect the reservoir assembly 602 with the base assembly 604.When the user connects the reservoir assembly 602 with the base assembly604, the mating piece 635 of the base assembly 604 pushes against theopening 642 of the covering 640 to close or block the opening 642. As aresult, fluidic media in the interior volume 615 of the reservoir 610can no longer flow out the port 612 to the chamber 650. The needle 630pierces the covering 640 to allow fluidic media contained in theinterior volume 615 of the reservoir 610 to flow through the needle 630to the base assembly 604 and then to the user. For example, fluidicmedia could flow from the interior volume 615 of the reservoir 610through the needle 630 into a fluid path (such as 190 in FIG. 7A) in thebase assembly 604 and to the user by way of a cannula (such as 194 inFIG. 7A).

The mating piece 635 may securely cover or block the opening 642 toprevent fluidic media from flowing out the opening 642 while thereservoir assembly 602 and the base assembly 604 are connected. In someembodiments of the present invention, the mating piece 635 may close orotherwise seal off the chamber 650, thus inhibiting fluidic mediacontained in the chamber 650 from flowing back into the interior volume615 of the reservoir 610 or otherwise flowing out of the chamber 650.

In further embodiments, the needle 630 may be positioned to enter theopening 642 in the covering 640 and to enter the interior volume 615 ofthe reservoir 610 when the reservoir assembly 602 and the base assembly604 are connected by the user. In yet further embodiments, the valve 645may be pierced by the needle 630 when the reservoir assembly 602 and thebase assembly 604 are connected by the user. In some embodiments, theneedle 630 has a diameter comparable to a diameter of the opening 642 sothat the needle 630 seals the opening 642 when the needle 630 enters theopening 642.

The embodiments disclosed herein are to be considered in all respects asillustrative, and not restrictive of the invention. The presentinvention is in no way limited to the embodiments described above.Various modifications and changes may be made to the embodiments withoutdeparting from the spirit and scope of the invention. The scope of theinvention is indicated by the attached claims, rather than theembodiments. Various modifications and changes that come within themeaning and range of equivalency of the claims are intended to be withinthe scope of the invention.

What is claimed is:
 1. A system for controlling pressure in a fluidreservoir, the system comprising: a housing structure having an interiorvolume; a pierceable member having a hollow interior volume, a first endand a second end, the pierceable member arranged in the interior volumeof the housing structure, for movement relative to the housing structurefrom a first position to a second position; and a hollow needle arrangedto be connected in fluid flow communication with the fluid reservoir,the hollow needle having a longitudinal dimension and a piercing endarranged within the hollow interior volume of the pierceable member whenthe pierceable member is in the first position, the piercing end of thehollow needle piercing through the first end of the pierceable memberwhen the pierceable member is moved from the first position to thesecond position; the interior volume of the pierceable member beingexpandable to increase the size of the hollow interior volume of thepierceable member, in response to an increase in fluid pressure withinthe hollow interior volume of the pierceable member.
 2. A system asrecited in claim 1, wherein the pierceable member has an inner surfacesurrounding the hollow interior volume of the pierceable member, theinner surface of the pierceable member extending along the longitudinaldimension of the hollow needle and bowing outward to define a concavecurvature along the longitudinal dimension of the hollow needle.
 3. Asystem as recited in claim 1, wherein the hollow needle has a firstopening arranged within the hollow interior volume of the pierceablemember when the pierceable member is in the first position, such thatfluid flowing through the hollow needle from the reservoir when thepierceable member is in the first position is expelled through the firstopening of the hollow needle and retained within the hollow interiorvolume of the pierceable member.
 4. A system as recited in claim 3,wherein fluid flowing through the hollow needle from the reservoir whenthe pierceable member is in the second position is expelled through thefirst opening of the hollow needle to a location outside of the interiorvolume of the pierceable member.
 5. A system as recited in claim 1,wherein the pierceable member includes a membrane wall that expands toincrease the size of the hollow interior volume, in response to anincrease in fluid pressure within the hollow interior volume of thepierceable member.
 6. A system as recited in claim 5, wherein themembrane wall comprises an elastic material.
 7. A system as recited inclaim 5, wherein the membrane wall inhibits passage of fluid out fromthe hollow interior volume of the pierceable member.
 8. A system asrecited in claim 5, wherein the membrane wall uses a hydrophobic orhydrophilic material to allow for pressure equalization across themembrane wall.
 9. A system for controlling pressure in a fluidreservoir, the system comprising: a housing structure having an interiorvolume; a pierceable member having a hollow interior volume, a first endand a second end, the pierceable member arranged in the interior volumeof the housing structure, for movement relative to the housing structurefrom a first position to a second position; and a hollow needle arrangedto be connected in fluid flow communication with the fluid reservoir,the hollow needle having a longitudinal dimension and a piercing endarranged within the hollow interior volume of the pierceable member whenthe pierceable member is in the first position, the piercing end of thehollow needle piercing through the first end of the pierceable memberwhen the pierceable member is moved from the first position to thesecond position; wherein the housing structure includes a chamber thatis outside of the hollow volume of the pierceable member, but in fluidflow communication with the hollow volume of the pierceable member, forreceiving fluid from the hollow volume of the pierceable member, upon athe hollow interior volume of the pierceable member receiving a volumeof fluid that is greater than the hollow volume of the pierceablemember.
 10. A system as recited in claim 9, wherein the chamber of thehousing structure is arranged to receive fluid from the hollow volume ofthe pierceable member, upon a volume of fluid expelled from the firstopening of the hollow needle into the hollow interior volume of thepierceable member exceeding the hollow volume of the pierceable member.11. A system as recited in claim 9, wherein the pierceable member has aninner surface surrounding the hollow interior volume of the pierceablemember, the inner surface of the pierceable member extending along thelongitudinal dimension of the hollow needle and bowing outward to definea concave curvature along the longitudinal dimension of the hollowneedle.
 12. A system as recited in claim 9, wherein the hollow needlehas a first opening arranged within the hollow interior volume of thepierceable member when the pierceable member is in the first position,such that fluid flowing through the hollow needle from the reservoirwhen the pierceable member is in the first position is expelled throughthe first opening of the hollow needle and retained within the hollowinterior volume of the pierceable member.
 13. A system as recited inclaim 12, wherein fluid flowing through the hollow needle from thereservoir when the pierceable member is in the second position isexpelled through the first opening of the hollow needle to a locationoutside of the interior volume of the pierceable member.
 14. A methodfor controlling pressure in a fluid reservoir, the method comprising:providing a housing structure having an interior volume; supporting apierceable member in the interior volume of the housing structure formovement relative to the housing structure from a first position to asecond position, the pierceable member having a hollow interior volume,a first end and a second end; and arranging a hollow needle to beconnected in fluid flow communication with the fluid reservoir, thehollow needle having a longitudinal dimension and a piercing end,wherein arranging the hollow needle further includes arranging thepiercing end of the hollow needle within the hollow interior volume ofthe pierceable member when the pierceable member is in the firstposition; piercing through the first end of the pierceable member withthe piercing end of the hollow needle when the pierceable member ismoved from the first position to the second position; and expanding theinterior volume of the pierceable member, in response to an increase influid pressure within the hollow interior volume of the pierceablemember.
 15. A method as recited in claim 14, wherein the pierceablemember has an inner surface surrounding the hollow interior volume ofthe pierceable member, the method further comprising bowing outward theinner surface of the pierceable member that extends along thelongitudinal dimension of the hollow needle to define a concavecurvature along the longitudinal dimension of the hollow needle.
 16. Amethod as recited in claim 14, further comprising arranging a firstopening in the hollow needle within the hollow interior volume of thepierceable member when the pierceable member is in the first position,such that fluid flowing through the hollow needle from the reservoirwhen the pierceable member is in the first position is expelled throughthe first opening of the hollow needle and retained within the hollowinterior volume of the pierceable member.
 17. A method as recited inclaim 16, arranging the first opening in the hollow needle in a locationoutside of the interior volume of the pierceable member when thepierceable member is in the second position so that fluid flowingthrough the hollow needle from the reservoir when the pierceable memberis in the second position is expelled through the first opening of thehollow needle to the location outside of the interior volume of thepierceable member.
 18. A method as recited in claim 14, furthercomprising providing the pierceable member with a membrane wall thatexpands to increase the size of the hollow interior volume, in responseto an increase in fluid pressure within the hollow interior volume ofthe pierceable member.
 19. A method as recited in claim 18, wherein themembrane wall comprises an elastic material.
 20. A method as recited inclaim 18, further comprising using hydrophobic or hydrophilic materialfor the membrane wall to allow for pressure equalization across themembrane wall.
 21. A method for controlling pressure in a fluidreservoir, the method comprising: providing a housing structure havingan interior volume; arranging a pierceable member in the interior volumeof the housing structure, for movement relative to the housing structurefrom a first position to a second position, the pierceable member havinga hollow interior volume, a first end and a second end; and arranging ahollow needle to be connected in fluid flow communication with the fluidreservoir, the hollow needle having a longitudinal dimension and apiercing end, wherein arranging the hollow needle further includesarranging the piercing end of the hollow needle within the hollowinterior volume of the pierceable member when the pierceable member isin the first position; piercing through the first end of the pierceablemember with the piercing end of the hollow needle when the pierceablemember is moved from the first position to the second position; andproviding a chamber in the housing structure, the chamber being outsideof the hollow volume of the pierceable member, but in fluid flowcommunication with the hollow volume of the pierceable member, forreceiving fluid from the hollow volume of the pierceable member, upon athe hollow interior volume of the pierceable member receiving a volumeof fluid that is greater than the hollow volume of the pierceable member22. A method as recited in claim 21, further comprising arranging thechamber of the housing structure to receive fluid from the hollow volumeof the pierceable member, upon a volume of fluid expelled from the firstopening of the hollow needle into the hollow interior volume of thepierceable member exceeding the hollow volume of the pierceable member.23. A method as recited in claim 21, further comprising providing thepierceable member with an inner surface surrounding the hollow interiorvolume of the pierceable member, the inner surface of the pierceablemember extending along the longitudinal dimension of the hollow needleand bowing outward to define a concave curvature along the longitudinaldimension of the hollow needle.
 24. A method as recited in claim 20,further comprising arranging a first opening of the hollow needle withinthe hollow interior volume of the pierceable member when the pierceablemember is in the first position, such that fluid flowing through thehollow needle from the reservoir when the pierceable member is in thefirst position is expelled through the first opening of the hollowneedle and retained within the hollow interior volume of the pierceablemember.
 25. A method as recited in claim 24, wherein fluid flowingthrough the hollow needle from the reservoir when the pierceable memberis in the second position is expelled through the first opening of thehollow needle to a location outside of the interior volume of thepierceable member.